Process and apparatus for controlling shrinkage in and otherwise improving the characteristics of tubular fabrics



5 Sheets-Sheet 1 N. WEHRMANN OF TUBULAR FABRICS OTHERWISE IMPROVING THE CHARACTERISTICS PROCESS AND APPARATUS FOR CONTROLLING SHRINKAGE IN AND Filed May 29, 1958 Nov; I 7.,

N Awazns Nov. 7, 1961 N. WEHRMANN 3 PROCESS AND APPARATUS FOR CONTROLLING SHRINKAGE IN AND OTHERWISE IMPROVING THE CHARACTERISTICS OF TUBULAR FABRICS Filed May 29, 1958 5 Sheets-Sheet 2 1 QT I 24 VENT R. g Mas 0M: zwinzwfi 1961 N. WEHRMANN PROCESS AND APPARATUS FOR CONTROLLING SHRINKAGE IN AND OTHERWISE IMPROVING THE CHARACTERISTICS OF TUBULAR mamas 5 Sheets-Sheet 5 Filed May 29, 1958 I I I I I I I I n u I INVENTOR. Male 04,4: IMWPMJ/VA/ Mk M3, MW mw Nov. 7., 1961 N. WEHRMANN 3,007,223

PROCESS AND APPARATUS FOR CONTROLLING SHRINKAGE IN AND OTHERWISE IMPROVING THE CHARACTERISTICS OF TUBULAR FABRICS 5 Sheets-Sheet 4 1 CIA L 00 a3 Filed May 29, 1958 Ai/a /3/- 5/6 INVENTOR. Mas 04,4: Wave/144mm NOV 7, 1961 N. WEHRMANN 3,007,223

PROCESS AND APPARATUS FOR CONTROLLING SHRINKAGE IN AND OTHERWISE mpaovmc THE CHARACTERISTICS OF TUBULAR FABRICS Filed May 29, 1958 5 Sheets-Sheet 5 INVENTOR Move; 4: Mq/PMw/v AT RNEY5I United States Patent Office 3,607,223 Patented Nov. 7, 1961 3,007,223 PROCESS AND APPARATUS FOR CONTROLLING SHRINKAGE IN AND OTHERWISE IMPROVING THE CHARACTERISTICS OF TUBULAR FABRICS Nicholas Wehrmann, North Wilkesboro, N.C., assignor to L. & L. Manufacturing, Inc., a corporation of Delaware Filed May 29, 1958, Ser. No. 738,693 30 Claims. (Cl. 2618.6)

This invention relates to the preshrinking of tubular fabrics and to the provision of finished tubular fabrics having improved characteristics.

This application is a continuation-in-part of my copending application Serial No. 689,112, filed October 9, 1957, and now abandoned.

The shrinkage of garments is caused in large measure by a tendency of the yarns of which the garment is formed and of the loops of the yarn of knitted fabric to return to a normal relaxed condition after they have been stretched during the knitting, dyeing, washing, and other treatments to which the fabric is subjected prior to being made up into garments. Since the stretching during processing is usually longitudinal stretching, preshrinking should involve a longitudinal compacting of the fabric.

During the normal process of dyeing or bleaching knitted fabrics, the yarns and loop formations would absorb their normal degree of shrinkage if the fabric were allowed to dry in a relaxed condition. Subsequent finishing operations, however, greatly distort this fabric in a longitudinal direction. This longitudinal stretching during subsequent processing often amounts to an increase of or sometimes in the length of the fabric over what the length would have been had it been allowed to dry in a relaxed state after the bleaching or dyeing process, but before the remaining finishing processes, all of which cause some degree of tension on the fabric.

Extensive experiments have shown that the prime factor in shrinkage control is the ratio between the number of loops per unit of length before and after the finishing processes. That is to say that total length shrinkage decreases in almost the same ratio as the number of loops per unit of length increases between the time when the fabric is in the knitted but unfinished stage and the time when it is a finished fabric.

In order, therefore, to effectively prevent shrinking, a fabric should be treated so as to restore the yarns to their relaxed condition and to incease the number of loops per unit of length, which in effect produces a finished fabric similar to fabric which is shrunk by washing and mechanical drying after it is embodied in a garment.

While various suggestions have been made for longitudinally compacting tubular knitted fabrics by propelling a portion of the fabric at a differential speed, none have achieved a sufficient restoration of both the fibres and the loops from their stretched condition, nor have they achieved sufficient uniformity of restoration. In certain of them also, additional distortions are introduced.

In knitted fabrics, moreover, the ratio of fullness of the fabric to the size of the yarn used is often smaller than desirable. When knitting relatively thin yarns, it is often difficult to provide fabrics having as great a fullness in the plane of the fabric as is desirable in a number of instances. Moreover, ordinary knitted fabrics tend to show light lines thereacross where light ends of yarn are present, and the elasticity of the fabrics tends to be predominantly in one direction to an undesirable degree; and in finished jersey knit tubular fabrics there is an undesirable tendency for the edges to curl.

With the foregoing and other considerations in view, the present invention contemplates the provision of highly effective, uniform, simple, and efficient procedures and apparatus for the preshrinking of fabrics and otherwise improving their characteristics.

In certain of its aspects, the present invention utilizes the principle that the inner surface of an endless belt moves at the same speed at the turns as at the straightaway portions; but that the outer surface at the turns of a belt of substantial thickness moves at a greater speed than does the inner surface, whereas the outer surface moves at only the same speed as the inner surface at the straightaway portions. Consequently, a portion of a fabric first propelled by the rearward turn of the outer surface of an endless belt and later by a straight-line portion thereof will be first moved at a relatively high speed and later at a relatively low speed, and will accordingly be longitudinally contracted in an exceedingly simple and effective manner. Moreover, by contacting the sides of a tubular fabric with such successive portions of the belt throughout the entire lateral extents of the sides of the fabric, an exceedingly uniform longitudinal contraction can be obtained.

In carrying out the invention and in the provision of apparatus embodying the invention, there may effectively be employed belts which have a thickness which is a relatively large fraction (e.g., to A) of the diameter of the rollers on which the belts turn, which have firm outer surfaces, and, at least throughout the outer portion thereof, such elasticity, stretch-ability, or expandability that the increase in the speed of the outer surfaces at the turns will be substantially confined to the turns. Desirably the inner portion of such a belt should have a minimum of such stretchability, this minimizing of stretchability being obtained by providing the usual wire or cloth reinforcing means at the inner portion, such means being omitted at the outer portion.

Considered from another aspect, the invention contemplates pressing a tubular fabric between the straight runs of endless belts at a relatively low speed while it is fed thereto throughout its lateral extent at a relatively high speed.

Considered in still another aspect, the invention contemplates the compression of a tubular fabric between upper and lower belts under conditions such that at least certain of various desirable characteristics are imparted to the fabric including an increase in the elasticity factor both lengthwise and widthwise, a conversion of the yarns thereof from circular to a more elliptical cross-section with consequent improved fullness of appearance and an increase in uniformity of appearance.

Other features of the invention in various of its more specific aspects will appear hereinafter.

The invention accordingly comprises the several steps and the relation and order of one or more of such steps with respect to each of the others, and the apparatus embodying features of construction, combinations of elements and arrangement of parts which are adapted to effect such steps, all as exemplified in the following detailed disclosure, and the scope of the application of which will be indicated in the claims.

For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawings, in which:

FIGURE 1 is a side view of one form of device embodying the invention and exemplifying the procedure:

FIG. 2 is an enlarged fragmentary side view mainly in section;

FIG. 3 is a fragmentary top view, with the fabric omitted, on the scale of FIG. 1;

FIG. 4 is a perspective view of the fabric-receiving form on a reduced scale;

FIG. 5 is a fragmentary side view of a fabric-receiving form having a modified shape;

FIG. 6 is a similar view of a fabric-receiving form having a differently modified shape;

FIG. 7 is a fragmentary view of a greatly enlarged belt section;

FIG. 8 is a fragmentary view of the device such as shown in FIG. 1, showing a modification;

FIG. 9 is a partly sectional side view of another form of device embodying the invention and exemplifying the procedure;

FIG. 10 is a perspective view of a detail of the device of FIG. 9;

FIG. 11 is an end view taken from the left of FIG. 9;

FIG. 12 is a partly sectional end view taken from the right of FIG. 9;

FIG. 13 is an enlarged detail view of certain of the elements of FIG. 12;

FIG. 14 is a top view of the elements of FIG. 13;

FIG. 15 is an enlarged partly sectional detail view showing the overfeed rollers;

FIG. 16 is a sectional view along the line 16-16 of FIG. 15;

FIG. 17 is a detail perspective view of a pressure roller;

FIG. 18 is a similar view showing mechanism including the roller of FIG. 17;

FIG. 19 is a perspective view showing the form-alining means;

FIG. 20 is a fragmentary enlarged plan view thereof;

FIG. 21 is a perspective view of the mechanism for adjusting the entry angle of the belts;

FIG. ,22 is a fragmentary sectional view thereof; and

FIG. 23 is a fragmentary view of an alternative type of belt.

The device exemplified in FIGS. 1-7 comprises a pair of endless belts 10 and 12 moving, respectively, on rearward rollers 14 and 16 and on forward rollers 18 and 20. The rollers in the present instance are one inch in diameter and the belts three-sixteenths of an inch in thickness. The belts are formed of suitable solid and firm material such as rubber, flexible solid plastic, or the like, so that at least the exterior portions thereof are stretchable and provide firm outer surfaces having a relatively high coefficient, of friction. As exemplified, each belt is formed of solid (not sponge) rubber having a firm outer surface 22, a stretchable exterior portion 24 which is one eighth of an inch in thickness, and an interior portion 25 which is reinforced by cloth or wire 26. This construction provides sufiicient yieldability in the exterior portion of each belt so that the rearward semi-circular surface of the belt which moves over a rearward roller will stretch enough so as to provide a surface moving at a greater speed than the exterior ofrthe'roller and the outer surfaces at the straight portions of the belt.

Floating freely between the belts is a form 28 which has relatively smooth surfaces, and which may be composed, for example, of thermosetting resin suitably reinforced with fibrous material, of metal, or of other hard material providing a slip surface. The form 28 is adapted to receive a tubular fabric which may be moved thereover from left to right, as shown. The form 28 comprises a thin and, preferably, wide forward portion 30 which is of uniform width, in the present instance, and which lies between the proximate straight portions of the belts, a thicker and narrower portion 32 lying rearward of the belts, and a joining portion 34 connecting the portions 30 and 32. As exemplified, the portion 30 is one sixteenth of an inch thick. The actual width of the portion 30 will depend on the width of the flattened tube of fabric, but should be no greater than the width of the belts, and, as exemplified, is twenty inches, the belts being shown as thirty inches wide. The distance from axis to axis of the rollers for 'each belt is, as exemplified, sixty inches. As exemplified, the portion 32 is of somewhat less thickness than the distance between the axes of the rollers 14 and 16, but may be as thick as this distance. The portion 34 is constructed to hold the sides of a tubular fabric 35 between curved surfaces 36 and 37 thereon and the outer surface of each belt at least on a line 38 which is in the plane of the axes of the rollers and on a line 40 disposed substantially rearwardly of this plane, and, as exemplified in FIGS. 1-4, against the turns of the belts along the curved surfaces 36 and 37 the entire distance between these lines.

The portion 34 is sloped outwardly at its edges 41 and 42 to smoothly join the edges of the portion 34 to the portion 30. The portion 30 extends between the plane of the axes of the rearward rollers 14 and 16 and the plane of the axes of the forward rolleres 18 and 20. As will be seen, the sum of the lateral and transverse extents of the portion 30 is the same as the sum of those of the portion 32, and the portion 34 similarly conforms, so that the tubular fabric will have the same circumferential extent at all parts of the form. In other words, the peripheral extent of the portion 34 i the same throughout its entire extent from the plane at which it meets the portion 32 to the plane at which it meets the portion 30, and the peripheral extents of the portions 30 and 32 are, in the present instance, the same as that of the portion 34. Thus the fabric is neither stretched laterally nor allowed to shrink laterally while on the portion 34, nor, in the present instance, while on any part of the entire form. Since the peripheral extent of the fabric is unaltered, the longitudinal and transverse compaction of the fabric may proceed under perfect control and free from lateral tensions. It is of importance that the sum of the lateral and transverse extents of the form remain the same at all cross-sections thereof from a plane through the thick portion to a plane through the thin portion, so that the form will cause no lateral stretching and permit no lateral contraction of the tubular knitted fabric during the treatment.

In certain instances, the portion 34 may be formed as exemplified in FIG. 5, with flat forward surfaces 43, so that the fabric is free to extend without friction between the lines of contact 45 and 46. Alternately, these surfaces may be formed as shown in FIG. 6, in smoother curves 47 which hold the fabric against each belt on lines 48 and 50.

Form 28 is held in position with the portion 34 there of pressed against the fabric 35 and the fabric pressed against the stretched parts of the belts at the turns there of by the action of the belts pulling the form 28 forwardly through the apparatus until the surfaces 36 and 37 are held snugly against the fabric to hold it against the stretched parts at the curves of the belts, after which form 28 can no longer travel with the belts. The fabric is therefore fed into the device at the rate of speed that the outside of the belts are traveling at the point of contact with surfaces 36 and 37. Due to the stretched condition of the turns of the belts, this speed is substantially more than the speed of each belt at its straight-away portion.

Since the coefficient of friction between the belts and the fabric is much greater than that between the fabric and form 28, the fabric is propelled with the belts so that the initial point of contact between the fabric and belt will remain the same throughout the operation. This relative coefficient of friction, together with the uniformity of lateral pressure, also keeps the fabric from spreading widthwise during the compacting of the fabric, which provides a control of width shrinkage.

The rollers of the respective belts may be adjustably mounted as shown at 51 to accommodate different thicknesses of fabric satisfactorily between the straight runs of the belts.

The fabric is pressed against the portion 30 by the proximate straight runs of the belts either by their own inherent tension or by suitable means such as springpressed rolls 52.

By providing belts which are as wide as or wider than the portion of the form exemplified at 30, and whichcontact the fabric throughout its width, a positive control over width shrinkage is provided. Tubular knitted fabrics have a tendency to widen when longitudinal-1y compacted; but in an arrangement such as exemplified nowidening is permitted because of the continuous pressure of the straight runs of the belts against the sides of the fabric.

Driving means 53 is provided, being indicated diagrammatically as including chains 54 and reduction gearing the upper large gear of which in shown at 55.

Steam boxes 56 and 57 are provided for ejecting steam onto the fabric, when necessary, before it contacts the belts, so that the fabric when it moves against the belts will be in a wet warm condition in which both the threads and the loops can be contracted. After leaving the belts and 12 and the form 28, the fabric may be passed between steam rolls 58 and 60 (which have the same peripheral speed as the lineal speed of the straight-run portions of the belts 10 and 12), and/or between drying boxes 62 and 64 from which compressed and/or hot air is ejected onto the sides of the fabric, or may be passed through other drying means or otherwise dried, after which it may be folded (as exemplified) or rolled up in the usual manner for storage in a preshrunk condition caused by the slowing down of the speed of its travel as it ran between the straight portions of the belts at the sides of the form.

'In general, it may be said that the percentage of overfeed in a device such as that exemplified is equal totwice the thickness of'the free, elastic outer portion of the belt divided by the sum of the diameter of the roller and twice the thickness of the inner inelastic portion of the belt. By proper selection of belts for desired overfeeds, various percentages of stretch can be taken up. For example, 20% shrinkage potential can be taken up by a belt such as exemplified; 15% shrinkage potential, by a belt having an outer portion three thirty-seconds of an inch in thickness, other dimensions being unchanged; and 10% shrinkage potential, by a belt having an outer portion of one sixteenth of an inch in thickness, other dimensions being unchanged. Some variations will ensue, due to the reduction in thickness of the belt as it stretches at the turn and other factors, and some increase in overfeed over that calculated may be desirable,

If greater preshninking is desirable under any particular conditions, the fabric may be run over apparatus such as exemplified, or otherwise contemplated, by the invention, then run over a duplicate or similar apparatus disposed in line with the first; or, indeed, may be run twice over the same apparatus.

The length of the stnaight-rutn portions of the belts should be sufiicient to 'allow the wet fabric to set in its preshrunk condition before leaving the belts. For example, when the speed of the belts at their straight-run portions is twenty linear yards per minute, the length of the belts, .center-to-center, should be thirty inches, or for forty yards per minute, sixty inches as exemplified. The speeds of the belts should, of course, be exactly coordinated.

Forms of different widths, but less than the width of the belts, may be used by the same belts for the treatment of tubular fabrics of varying tubular diameters.

Advantageously in certain instances the fabric may, as shown in FIG. 8, be drawn from the belts 10 and 12 thru an oven 68 by solid rollers 70 and 72 having a peripheral speed which is the same as the lineal speed of the straight-run portions of the belts 10 and I12. The oven 68 may be heated by any suitable means as by electric heaters 71 to a temperature ranging from above the boiling point of water to 300*" F. or higher, depending on the deterioration temperatureof the yarn of which the fabric is formed. Temperatures of from 2250 to 270 F. have been found generally satisfactory.

I have found, however, that exception-ally effective results can be obtained by heating the fabric to dry it while it is between the belts. This is advantageously accomplished, pursuant to the invention in certain of its more specific aspects, by heating the belts, as by enclosing all or part thereof in an oven as hereinafter exemplified.

I have also found that it is desirable to reduce the extent of the arc of the belts at their turns for use under varying conditions. This is due to tendencies for the stretch of the outer surfaces of the turn of a belt to be in part transmitted to a straight-run portion on both sides of the turn, and to be thereby decreased at the portions of the turn adjacent thereto, so that the proportionate stretch .of the belt near each end of an extensive turn will be less than the stretch near the center of such a turn. It will thus be seen that if the arc of the turn is small, the full stretch at the center may be eliminated entirely, and the speed of the entire outer surface of the belt at the turn reduced. Accordingly, if a belt is fed to a roller such as 14 at a small enough angle to the horizontal top surface of the thickened portion of a form element such as shown at 32 so that the initial line of contact of the belt with the roller is near to the initial line of contact of the fabric with the belt, the speed of the outer surface of the belt at the line of initial contact with the fabric may be less than its speed when it is fed to the roller at a greater angle; and I have utilized this principle, pursuant to certain aspects of the invention, by providing means for feeding the belts in at small angles in instances where lesser speeds will be effective and where undue stretch causes undue wear on the belts and of means for varying the angle of feed of the belts to the rollers in instances where different speeds of the belts at the lines of initial contact with the fabric are desirable when fabrics which have had an undesirable stretch of a greater or less extent imparted thereto prior to treatment are being treated.

I have also found that the varying speeds of belts at their turns and at their straight runs may be utilized to provide a control at the end of the treatment whereby the execessive longitudinal compression of the fabric as may sometimes result from the action thereon of the belts may be reduced when desired.

In addition, I have provided various operations and structural improvements which, together with the fore going, are exemplified in the embodiments of the invention hereinafter described.

In the form of construction exemplified in FIGS. 922, there is provided a belt 89 similar to the belt 10 and a belt 82 similar to the belt 12 but extending beyond the far end of the belt for reasons to be discussed hereinafter. The belts 80 and 82 are one fourth of an inch thick as exemplified. One or both of the belts may, in certain instances, be of foraminate construction as shown at 82a in FIG. 23, being provided with holes 8% therethrough. The belts 80 and 82 are fully enclosed by an oven 83, in the present instance, except for an entrance opening 83a for the reception of a tubular fabric 84 on a form 85 after the fabric passes between steam boxes 86 and 87 similar to the steam boxes 56 and 5'7, and except for the far ends of the belts which project thru an opening 89 in the rear end of the oven 83. The oven 83 may be heated, as by electric heaters 90, to heat the belts so that they will dry and tend to set the moist fabric as it is compressed between their straight runs. The projection of the far end of the belts from the oven serves to permit them to make their reverse turns in a cool atmosphere, which results in longer wear, and also serves purposes hereinafter to be set forth.

A rear drive roller 93, which is three inches in diameter and driven from a suitable source of power, is provided for operating the belt 80, and a similar rear drive roller driven at the same speed as the roller 93 is provided for operating the belt 82. At their forward ends, the belts 80 and :82 run over idler rollers 97 and 98, respectively. The rollers 97 and 98 are one inch in diameter, as exemplified. The distance between the axes of the rollers 93 and 97 is eighty-two inches in the present instance, and the distance between the axes of the rollers 95 and 98 is ninety- 7 four inches in the present instance. In order to assure against bowing of the rolls 97 and 98, each is backed by an anchor pillow block bearing 99 of graphitized bronze which is bolted to the frame.

In order to control the stretch of the belts as they go over the rollers 97 and 98 and to control the outside speed of the belts on the lines where they contact the fabric, there are provided, in advance of and outside of the rollers 97 and 98, idler rollers 100 and 101 which, preferably and as exemplified, are one inch in diameter and are adjustable to vary the angle between them and the rollers 97 and 98 respectively by a movement which will not vary the tautness of the belts. In the present instance, a circular bearing 102 at each end of the roller 100 rides on the contoured upper surface 104 of a control element 105, and a circular bearing 107 at each end of the roller 101 rides on the contoured lower surface 108 of a control element 109. The surfaces 104 and 108 are contoured, as shown, to assure that the belt 80 will, at all times, be held taut between the rollers 93, 100, and 97, and the belt 82 will, at all times, be held taut between the rollers 95, 101, and 98. Adjustment of the position of the rollers 100 and 101 along the surfaces 104 and 108, respectively, is accomplished by two units, one at each side of the belts 80 and 82, and each comprising two blocks 111 and 112 having openings 113 and 114 therein thru which the rollers 100 and 101, respectively, extend. In each unit a rod 118 having an upper left-hand thread 119 and a lower right-hand thread 120 extends thru the blocks 111 and 112, respectively, with its respective threads engaging cooperatively-formed inner threads therein. The center of the rod 118 is rotatably mounted in a sleeve 122 on the end of a rod 124 which is slidably mounted in a forwardly-mounted sleeve 125 and may be secured in place by a set screw 126. Each rod 118 is rotated by a sprocket 128, the sprockets 128 being connected by a chain 129 and operated by handles 130 as shown. The rollers 100 and 101 are shown in an extreme position in FIG. 21 to illustrate the mechanism more clearly. Ordinarily these rollers will be in positions at or between the two positions for each shown in dot-and-dash lines in FIG. 22. The rollers are illustrated in full lines in FIG. 22 in positions intermediate those shown in dot-and-dash lines. The speed at which the belts 80 and 82 will feed the fabric will decrease as the rollers 100 and 101 are moved from the right-hand dot-and-dash position in FIG. 22 to the left-hand dot-and-dash position, causing the belt to engage the rollers 97 and 98 at a decreasing angle, and thus causing less stretch of the belt at the turns. The oven casing is provided with a slot 130a to permit movement of the rod 118.

As will be seen, the rollers 97 and 98 are journaled in the pairs of elements 105 and 109, respectively. The elements 109 are fixed to the frame, in the present instance, while each element 105 is carried by a verticallyadjustable mounting member 131 under control of a threaded rod 131a rotatable in a bracket 131b, by a handle 1310, as shown, upon the loosening of the set screw 126, to permit the relative position of the rollers 97 and 98 (and of the elements 105 and 109) to be adjusted for accommodating different thicknesses of fabric.

The operative straight run of the belt 82 is supported by a series of rolls 132 which are rotatable on shafts 134 which extend thru vertical lower slots 135 in side pieces 136 and are individually held in vertically adjusted position therein by nuts 138. The operative straight run of the belt 80 is pressed toward the belt 82 by the weight of a series of rolls 142 which are rotatable on shafts 144 which ride freely in vertical upper slots 145 in the side pieces 136. The roll 142 furthest to the right (FIG. 9) is preferably and as exemplified equipped with adjustable means to hold the belt in a desired lower effective position when thin fabrics are being treated, this means in the present instance comprising thumb screws 146 adapted 8 to be adjusted to bear downwardly on the ends of the shaft 144 of this roll when desired.

The form 85 is similar to the form 28 except that it is narrowed at angles of 30 with the horizontal at the portions where it meets the belts; except that it extends only part way between the straight runs of the belts, terminating at a line 146 beyond which the rolls 142 serve to press the straight runs of the belts together to press the fabric tightly therebetween; and except that the initial (left-hand FIGS. 9, l9, and 20) portion thereof is contoured as shown in FIG. 19 so as to conduct the fabric onto the operative portion of the form (that portion to the right of the line 148 in FIG. 19) smoothly and in a controlled manner. It is to be noted that the transverse peripheral extent of the form is still the same at all portions of the form after the fabric contacts the belts, and, in the present instance, for a considerable distance prior thereto. The slight spaces between the form 85 and the belts and 82 and to the left (FIG. 22) of the plane thru the axes of the rollers 97 and 98 tends to facilitate a controlled longitudinal compression of the fabric, but without pleating, before it is transversely compressed between the straight-run portions of the belts. As the fabric leaves the form, the portions thereof which lay along the edges of the form will flatten out at each side of the portions of the fabric which lay at the top and bottom of the form, so that the fabric will extend an extra one thirtysecond of an inch laterally between the belts. There will thus be no widthwise stretching or compression, and there will be no wrinkling. The edges of the thin portion of the form are rounded.

The belts are held against sidewise slippage on the rollers 93 and 95, and 97 and 98, respectively, by the provision thereon of annular guide members 150 and 152, which, preferably and as exemplified, are slidably mounted on their respective rollers and are each retained in place thereon at the edge of a belt of any particular width by means of a set screw 154.

Sidewise movement of the form 85 is prevented by a pair of roller bearings extending against the fabric at the edges of the initial thickened portion of the form and held in place by rods 156 slidably fitted in fixed sleeves 158 and held therein by set screws 159 loosely enough to prevent any frictional drag on the fabric moving over the form.

The fabric 84, which comes in longitudinallycompacted and transversely-compressed form from beneath the upper belt 80 as the latter turns about the roller 93, continues to ride on the belt 82, and, pursuant to the invention in certain of its more specific aspects, may be wound upon a core 159 above the belt 82 to form a roll 160, which, once started, will continue to be rotated by the belt 82 at the same peripheral speed as the linear speed of the belt 82; the ends of the core, as exemplified, being slidably mounted by roller bearings 161 in vertical (in the full line position of FIG. 9) open-ended grooves 162 in guide members 164.

When the fabric, at the time it comes from under the belt 80, is longitudinally compacted to substantially the desired extent, the guides 164 may be in the position shown in full lines in FIG. 9, where the roll being formed contacts with the upper straight-line run of the belt 82. In instances, however, when a slightly excessive longitudinal compression, due, for example, to variations in humidity and temperature, may have been imparted to the fabric by the apparatus and procedure such as heretofore exemplified, the guides 164 may be swung from the position shown in full lines to the position shown in dotted lines in FIG. 9, or to a greater or less extent in such direction, so that the roll being formed will contact with the turn of the belt 82 about the roller 95 at a greater or less distance from the straight-line portion of the belt where the stretch and speed of the belt is suitably greater than at the line where the roll being formed contacts it when in the position shown in full lines. The turn of the belt will thus impart a somewhat greater peripheral speed to the roll being formed than the speed of the fabric as it moves from between the belts 80 and 82 and will thus give the fabric a slight longitudinal stretch which will compensate for such slightly excessive longitudinal compaction as may have been transmitted to it.

To this end, the guides 164 are pivotally mounted on the ends of the shaft 165 of the roller 95, and are adjustably mounted on an arm 166 pivoted at 167 and held in adjusted position by a thumb screw 168.

There is produced an exceptionally desirable type of flattened tubular knitted fabric which has been compacted longitudinally and compressed transversely without change in its lateral extent. These factors combine to give a desirable length-and-width elasticity, the loops are shorter, and the yarn is flattened from its normal circular cross-section, and these characteristics are set in the fabric by the heat and pressure to which it is subjected. Tendencies of the fabric to curl are greatly reduced, the ease of manufacture of garments from the fabric is increased, and the comfort of garments made from knitted fabric is greatly enhanced when the fabric is treated in accordance with the present invention.

The shafts 171 and 165, respectively, of the drive rollers 93 and 95 are adjustably mounted by mechanisms 173 and 175 to adjust the tension of the belts. The roller 93' is driven from an electric motor 176 by a chain 177 operating over sprockets 178 and 179, and the roller 95 from the roller 93 by chain 180 operating over sprockets 181 and 182. In order to maintain the chain 177 taut there is provided an idler sprocket 185 carrying a stud 186 slidably mounted in a slot 187 in bracket 188. The stud 186 is held in an adjusted position by a lock nut 190. Similar means are provided for maintaining the chain 180 taut. The entire assembly is portably mounted on casters 195 so that it can be moved to receive tubular fabric from various prior operations in a plant.

It is to be observed that modern types of tumble or spin dry operations tend to cause more severe shrinkage than those drying operations which were previously employed; and that, since procedures and machines such as contemplated by the present invention are utilizable to shrink a fabric to the greatest extent that shrinkage will occur under the most severe conditions, the employment thereof is' of especial advantage under modern conditions. Since certain changes in carrying out the above process and in the constructions set forth, which embody the invention, may be made without departing from its scope, it is intended that all matter contained inthe above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

Certain subject matter disclosed herein is disclosed and claimed in my copending application Serial No. 66,816, filed November 2, 1960.

What is claimed is:

l. The process of preshrinking tubular fabric which comprises continuously pressing opposite sides of the fabric against opposite sides of a laterally-extended form as the fabric is moved forwardly along the form at a relatively low speed between juxtaposed longitudinal ex-' tents of a pair of endless belts of suflicient thickness so that the exterior surfaces of the turns of the belts will move at a higher linear speed than the longitudinal extents of the belts, and feeding each of opposite sides of the fabric to said juxtaposed longitudinal extents of said belts at a relatively high speed by pressing, prior to the movement of the fabric between said juxtaposed longitudinal extents, each of spaced opposite sidesof the fabric against spaced converging arcuate exterior surfaces of rearward turns of the belts moving at said higher speed.

2. Apparatus for preshrinking tubular fabric which cornprises means'to draw the fabric forward in a shape, having fiat upper and lower spaced sides, at a relatively high speed, said means further bringing the sides toward each other while edge portions thereof are flattened as lateral extensions of the sides, and to thereupon move the fabric forwardly in a transversely-restricted state at a relatively low speed, said means comprising a pair of endless belts which have juxtaposed forwardly-moving straight-run portions and rearward turns and which are of substantial thickness and of greater lateral extent than the fabric and the outer surfaces of the turns of,which move at a higher speed than the straight-run portions thereof and also comprising means adapted to fit interiorly of the fabric for pressing the fabric against the faster-moving outer surfaces of said belts at the rearward turns thereof and for guiding said fabric toward the straight-run portions of the belts, the straight-run portions of the belts moving the longitudinally contracted fabric forwardly in a transversely restricted st-ate, whereby the fabric is longitudinally contracted and transversely compressed.

3. A process as set forth in claim 1 the fabric being in a wet state when moved at said relatively high speed and being dried thereafter.

4. A process as set forth in claim 3 the fabric being dried during its forward movement between said longidiverging continuation of said fabric-holding means while pressing it throughout its lateral extent thereagainst by means moving at a relatively high speed, and passing the fabric over a relatively-thin further continuation of said fabric-holding means at a relatively low speed while pressing it throughout its lateral extent against the sides thereof by a slower-moving portion of said moving means.

7. A process as set forth in claim 6 wherein the sides of the fabric are thereafter pressed directly against each other while moving forward at said relatively low speed.

8. Apparatus for longitudinally contracting and transversely compressing tubular fabric comprising a pair of endless belts having straight runs facing each other and adapted to receive and compress the fabric between them and to move it forwardly at a relatively low speed while being compressed therebetween, means providing a pair of curved surfaces over which said belts run toward saidstraight runs, said curved surfaces engaging substantial portions of said belts rearwardly of the fabric-compressing straight runs thereof and said belts having a substantial thickness whereby the outer surfaces of said portions of said belts will move at an increased linear speed as the belts make their turns over said pair of curved surfaces, and means adapted to fit interiorly of the fabric and of less lateral extent than the width of the belts for guiding the fabric toward the straight runs thereof and having spaced laterally-extending surface portions for pressing spaced sides of the fabric against faster-moving portions of the belts at the turns thereof, at least along lines spaced rearwardly of said straight runs of said belts, said straight runs being closer to each other than said lines are to each other, whereby the fabric will be fed into compressive relationship with said straight runs of said belts at a greater speed than it is moved forwardly between said straight runs to longitudinally compact the fabric between said straight runs.

9. Apparatus as set forth in claim 8 wherein there is provided means to set said fabric in its longitudinallycompac-ted and transversely-compressed condition.

10. Apparatus as set forth in claim 9 wherein means to steamthe fabric is provided rearwardly of said belts.

ll. Apparatusfor longitudinally contracting and transversely compressing tubular fabric comprising a pair of endless belts having straight runs facing each other and 11 adapted to receive and compress the fabric between them and to move it forwardly at a relatively low speed while being compressed therebetween, a pair of rollers over which said belts run to the fabric-compressing straight runs thereof, said rollers engaging substantial portions of said belts rearwardly of the fabric-compressing straight runs thereof and said belts having a substantial thickness whereby the outer surfaces of said portions of said belts Will move at an increased linear speed as the belts make their turns over said pair of rollers, means adapted to fit interiorly of the fabric and of less lateral extend than the width of the belts for guiding the fabric to the straight runs thereof and having spaced laterally-extending surface portions for pressing spaced sides of the fabric against faster-moving portions of the belts at the turns thereof at least along lines spaced rearwardly of said straight runs of said belts, said straight runs being closer to each other than said lines are to each other, whereby the fabric will be fed into compressive relationship with said straight runs of said belts at a greater speed than it is moved forwardly between said straight runs to longitudinally compact the fabric between said straight runs, and means to heat at least portions of said belts to heat the fabric between them.

12. Apparatus as set forth in claim 11 wherein the major portion of said belts and of the fabric between them is enclosed in an oven.

13. Apparatus as in claim 8 wherein the means providing a pair of curved surfaces comprises a pair of rollers.

14. Apparatus as in claim 13 wherein there are provided rearwardly of the aforesaid rollers adjustable guide rollers from which the respective belts run to the aforesaid rollers, and means for adjusting the position of said adjustable rollers to vary the angle at which the respective belts meet the first-mentioned rollers while maintaining said belts taut whereby the extents of the belts in contact with the first-mentioned rollers is controlled.

15. Apparatus for preshrinking tubular fabric comprising a pair of endless belts of substantial thickness and having juxtaposed longitudinal extents movable together in a forward direction, means providing a pair of rearwardly-disposed curved surfaces over converging portions of respective ones of which said belts turn, means for driving said belts at similar speeds, and laterally-extended fabric-conducting means of less lateral extent than the Width of said belts between and in close proximity to at least the rearward portions of said juxtaposed longitudinal extents and carrying fabric-receiving means of no greater lateral extent than the width of said belts for pressing, prior to the movement of the fabric between said longitudinal extents of the belts, spaced laterally-extending sides of a tubular fabric against spaced portions of the rearward turns of the respective belts the exterior surfaces of which are moving at a higher linear speed than the longitudinal extents of the belts, whereby the spaced sides of the tubular fabric are moved forwardly at a higher speed by the turns of said belts than by said longitudinal extents thereof and the fabric compacted longitudinally between the latter.

16. Apparatus as in claim 15 wherein said fabricreceiving means is of decreasing thickness and increasing width, and wherein the peripheral extent along successive portions of said fabric-receiving means and said fabricconducting means is substantially the same so that there will be no substantial lateral stretching or lateral compaction of the fabric while it is being longitudinally compacted.

17. Apparatus as in claim 15 wherein said belts have firm but stretchable outer portions which are of substantial thickness and the outer surfaces of which have a greater coefficient of friction than the surfaces of said fabric-conducting means.

18. Apparatus as in claim 17 wherein said belts are reinforced adjacent their inner surfaces.

19. Apparatus as in claim 15 wherein said belts press the fabric firmly against said fabric-conducting means.

20. Apparatus for preshrinking tubular fabric comprising a pair of endless belts having substantially parallel juxtaposed longitudinal extents movable together in a forward direction, said belts having firm but stretchable outer portions which are proximate at said juxtaposed extents, a pair of rearwardly disposed rollers over converging portions of respective ones of which said belts turn, means for driving said belts at similar speeds, a freely-floating fabric-receiving form having a thin portion lying between at least the rearward portions of said longitudinal extents and in close proximity thereto to hold the sides of a fabric thereon respectively against said longitudinal extents, said form providing a thick portion disposed rearwardly thereof and having a laterally-extending part adapted to be drawn by said belts into close proximity to spaced por tions of the exterior surfaces of the rearward turns of said belts which are moving at a higher linear speed than the juxtaposed longitudinal extents of the belts to hold thereagainst the sides of a tubular fabric moving forwardly toward said longitudinal extents, each of the belts being thicker than said thin portion, whereby a tubular fabric may be moved forwardly at a higher speed by the turns of said belts than by said longitudinal extents thereof and the fabric compacted longitudinally between the latter.

21. Apparatus as set forth in claim 20 wherein means tending to move at least one of the juxtaposed longitudinal extents of said belts toward the other thereof are provided.

22. Apparatus for longitudinally contracting and transversely compressing tubular fabric comprising a pair of endless belts having straight runs facing each other and adapted to receive and compress the fabric between them and to move it forwardly at a relatively low speed while being compressed therebetween, a pair of rollers over which said belts run to the fabric-compressing straight runs thereof, said rollers engaging substantial portions of said belts rearwardly of the fabric-compressing straight runs thereof and said belts having a substantial thickness whereby the outer surfaces of said portions of said belts will move at an increased linear speed as the belts make their turns over said pair of rollers, means to press substantially-flat spaced portions of the fabric against fastermoving portions of said belts at the turns thereof at least along lines spaced rearwardly of said straight runs of said belts, the straight runs of the belts being closer'to each other than said lines are to each other, prior to movement of the fabric between the fabric-compressing straight runs thereof, whereby the fabric will be fed into compressive relationship with said straight runs of said belts at a greater speed than it is moved forwardly between said straight runs to longitudinally compact the fabric between said straight runs, said belts being disposed one above the other and thelower one of said belts extending forwardly beyond the upper one of said belts, a forward roller over which the lower one of said belts turns, a rotatable core on which tubular fabric coming from between the straight runs of said belts and thereafter riding on said lower belt may be wound, and means to guide said core for movement in a selected one of a plurality of courses one of which extends toward the relatively slowmoving straight-run portion of the surface of said lower belt and another of which extends toward a faster-moving outer surface of the turn of said lower belt over said forward roller.

- 23. Apparatus for longitudinally contracting and transversely compressing tubular fabric comprising a pair of endless belts having straight runs facing each other and adapted to receive and compress-the fabric between them and to move it forwardly at a relatively low speed while being compressed therebetween, a pair of rollers over which said belts run to the fabric-compressing straight runs thereof, said rollers engaging substantial portions of said belts rearwardly of the fabric-compressing straight runs thereof and said belts having a substantial thickness whereby the outer surfaces of said portions of said belts will move at an increased linear speed as the belts make their turns over said pair of rollers, means to press substantiallyfiat spaced portions of the fabric against faster-moving portions of said belts at the turns thereof at least along lines spaced rearwardly of said straight runs of said belts, the straight runs of the belts being closer to each other than said lines are to each other, prior to movement of the fabric between the fabric-compressing straight runs thereof whereby the fabric will be fed into compressive relationship with said straight runs of said belts at a greater speed than it is moved forwardly between said straight runs to longitudinally compact the fabric between said straight runs, said belts being disposed one above the other and the lower one of said belts extending forwardly beyond the upper one of said belts, a forward roller over which said lower one of said belts turns, means to heat said fabric while between said belts, and means to wind said fabric in a roll on a forwardly-extending portion of said lower belt.

24. Apparatus as in claim 15 wherein said fabric-conducting means and said fabric-receiving means are provided by a freely-floating form having a relatively thin forward portion and a relatively thick rearward portion connected by a portion having a decreasing thickness and an increasing width in a forward direction, and wherein the peripheral extent along successive portions of said form is substantially the same.

25. Apparatusas in claim 24 wherein said connecting portion is arranged to hold the sides of the fabric against the turns of the belts along substantial portions of the extents of said turns extending rearwardly of said longitudinal extents.

26. Apparatus for shrinking tubular fabric comprising a pair of endless belts of substantial thickness and having juxtaposed longitudinal extents movable together in a forward direction and having rearward turns with outer surface portions which move faster than said longitudinal extents, means providing a pair of rearwardly disposed curved surfaces over converging portions of respective ones of which said belts turn, and fabric-guiding means of decreasing thickness and increasing width to press the sides of the fabric against faster-moving portions of said belts at the turns thereof along at least spaced straight lines and extending forwardly at least to a line in proximity to the juxtaposed longitudinal extents of the belts and having a uniform effective peripheral extent from said straight lines to the forward end thereof whereby there will be no lateral stretchingg or lateral compaction of the fabric while between said straight lines and said forward end.

27. Apparatus as set forth in claim 8 wherein means to heat the return runs of the belts are provided.

28. Apparatus for preshrinking tubular fabric comprising a pair of endless belts of substantial thickness and having juxtaposed longitudinal extents movable together in a forward direction, means providing a pair of rearwardly-disposed curved surfaces over converging portions of respective ones of which said belts turn, means for driving said belts at similar speeds, and laterally-extended fabric-conducting means of less thickness than the thickness of each belt and disposed between and in close proximity to at least the rearward portions of said juxtaposed longitudinal extents and carrying fabric-receiving means for pressing, prior to the movement of the fabric between said longitudinal extents of the belts, spaced laterally-extending sides of a tubular fabric against spaced moving portions of the rearward turns of the respective belts the exterior surfaces of which are moving at a higher linear speed than the longitudinal extents of the belts whereby the spaced sides of the tubular fabric are moved forwardly at a higher speed by the turns of said belts than by said longitudinal extents thereof and the fabric compacted longitudinally between the latter.

29. Apparatus for longitudinally contracting tubular fabric comprising a pair of endless belts having-juxtaposed longitudinal extents movable together in a forward direction, means providing a pair of rearwardly-disposed curved surfaces over converging portions of respective ones of which said belts turn, said belts having stretchable outer portions of substantial thickness whereby the outer surfaces of said belts as they make their turns over said curved surfaces will move substantially faster than the juxtaposed longitudinal extents of the belts, and fabricguiding means of no greater lateral extent than the width of the belts and having side surfaces which converge toward each other at least as rapidly as the turns of said belts to press the sides of the fabric thereon against spaced moving portions of the belts at the turns thereof at least along substantially straight lines spaced rearwardly of said longitudinal extents of the belts, said guiding means extending forwardly at least substantially to said juxtaposed longitudinal extents of the belts and said longitudinal extents being closer to each other than at least the rearward parts of said fabric-guiding surface portions are to each other, whereby the fabric will be fed into compressive relationship with said longitudinal extents of the belts at a greater speed than it is moved forwardly between said longitudinal extents to longitudinally compact the fabric between said longitudinal extents.

30. The process of preshrinking tubular fabric which comprises continuously pressing opposite sides of the fabric between juxtaposed longitudinal extents of a pair of endless belts of sufficient thickness so that the exterior surfaces of the turns of the belts will move at a higher linear speed than the longitudinal extents of the belts, and feeding each of opposite sides of the fabric to said juxtaposed longitudinal extents of said belts at a relatively high speed by pressing, prior to the movement of the fabric between said juxtaposed longitudinal extents, each of spaced opposite sides of the fabric against spaced converging arcuate exterior surfaces of rearward turns of the belts moving at said higher speed.

References Cited in the file of this patent UNITED STATES PATENTS 1,721,154 Huse July 16, 1929 2,021,975 Wrigley et a1. Nov. 26, 1935 2,060,664 Cohn Nov. 10, 1936 2,146,694 Wrigley et al. Feb. 7, 1939 2,522,663 Chatfield Sept. 19, 1950 2,589,344 Cohn et al. Mar. 18, 1952 2,849,781 Rosen Sept. 2, 1958 FOREIGN PATENTS 15,957 Great Britain of 1908 394,933 Great Britain July 6, 1933 712,427 Great Britain July 21, 1954 

